Embryotoxicity of microplastics, isolated and associated with copper, in zebrafish (Danio rerio)
摘要
Microplastics (MPs) can adsorb metals like copper (Cu), raising concerns about their combined presence in freshwater environments and the acute effects of this mixture on fish during their embryonic development. Thus, this study aimed to evaluate the effects of acute exposure to MP (20 µg l−1) and Cu (10 µg l−1), isolated and mixed (MP + Cu), in embryos of Danio rerio, up to 96 h post-fertilization (hpf). The results showed a high affinity of MPs for the embryonic chorion. When compared to the control, embryos from the Cu (72 hpf) and MP + Cu (72 and 96 hpf) groups showed a significant delay in the hatching rate. Larvae exposed to MP alone and MP + Cu, exhibited a significant decrease in heart rate (96 hpf). Cu accumulation was found to be similar in larvae exposed to Cu and MP + Cu. There was no increase in DNA damage following the exposures. This study highlights that MPs not only have a strong affinity for the embryonic chorion but also adversely affects the development of D. rerio embryos, both isolated and in combination with Cu. Delays in hatching and bradycardia following exposure to MP + Cu reduce larvae's ecological fitness in the wild, impacting their long-term viability.